South Australian farm grows vegetables in the middle of the desert using only sunlight and seawater

Spread over a sprawling 20-hectare area in the South Australian desert, Sundrop Farms is the first of its kind in the entire world to grow vegetables using only seawater and sunlight. The result of six, long years of research, the amazing indoor farm produces more than 17,000 tons of tomatoes each year, despite being located in the desert with very limited access to fresh water. Speaking about the brilliant facility, the team said:

A conventional greenhouse uses groundwater for irrigation, gas for heating, and electricity for cooling. A Sundrop greenhouse turns seawater and sunlight into energy and water. We then use sustainably sourced carbon dioxide and nutrients to maximize the growth of our crops.

The aim of the project is to grow foods, without the need for soil, fresh water or even conventional grid-based energy. Operational since 2014, the Port Augusta facility relies on seawater sourced from the nearby Spencer Gulf, situated around 2 km (or 1.24 miles) away. The water then undergoes a thorough desalination treatment in a special, on-site plant that runs on solar power.

The clean, salt-free water is used to irrigate crops, which are grown in coconut husks instead of soil. To keep them protected from the harsh summers, when temperatures often rise to over 48 degrees Celsius (approx. 118 degrees Fahrenheit), the roots of the crops are lined with seawater-soaked pieces of cardboard. During winters, the sun’s heat provides sufficient warmth for the plants’ survival and growth.

The carefully-maintained indoor conditions in turn eliminate the risk of pests, thereby bringing costs further. The energy required to drive the facility is produced by a specially-constructed field of 23,000 mirrors that direct sun’s rays onto a particular tower containing a generator. At present, the farm is connected to an electrical grid as a backup, although most of its operations are powered by solar energy. The team added:

We use the Sun’s energy to produce freshwater for irrigation. And we turn it into electricity to power our greenhouse to heat and cool our crops. Our ventilation also uses seawater to clean and sterilize the air, so it keeps bugs under control without the need for pesticides… These closed production systems are very clever. I believe that systems using renewable energy sources will become better and better and increase in the future, contributing even more of some of our foods.

The system, the developers believe, could benefit farmers residing in places with scarce fresh water, arid, infertile land and high energy prices. However, such a technology comes with its own set of disadvantages, including potential negative impact on the local flora and fauna. For instance, mirror-based solar facilities are believed to be responsible for the incineration and death of more than 6,000 birds every year in the United States alone.

Home to 180,000 tomato plants, the Sundrop farm was built as part of a $200 million project. To know more, watch the following video: